Cellulose-ether solvent and composition



I Patented Dec. 5, 1922.

STEWART J. GARROLL, OF ROCHESTER, NEW YORK, ASSIGNOR I0 EASTW KODAK COMPANY, OF ROCHESTER, NEW YORK, A CORPQRATION OF NEW YQRK.

CELLULOSE-EQHER SOLVENT AND CGMPOSITIOIRT.

No Drawing.

To allwhomz'tmay-concem; w

Be it known that I, STEWART J. CARROLL, a citizen of the United States of America, residing at Rochester, in the county of Monroe and State of New York, have invented certain new and useful Improvements in Cellulose-Ether Solvents and Compositions of which the following is a full, clear, an exact specification.

lhis invention relates to solvents for making strong solutions of cellulose ether and also relates to the cellulose ether compositions produced by the aid of such solvents. One object of my invention is to provide a solvent which will dissolve such large proportions hf cellulose ethers that thicker viscous flowable solutions may be obtained for use in plastic and film making arts. Another object of my invention is to provide a cellulose ether solution which may be manufactured into strong, flexible transparent film on the machines and by the methods now in use.

In U. S. Patent No. 1,188,376, Lilienfeld, June 20, 1916, there are disclosed a series of alkyl ethers of cellulose. Certain of these are practically insoluble in Water, and my invention relates but is not limited to the ethers having that property. While the ethers form thin solutions in ethyl alcohol and the like, it has been found that such single solvents by themselves dissolve in general only a small pro rtion of the ethers, so that it is not possib e to make a desirably thick flowable composition or dope which may, for example, be used in the manufacture of photographic film base by customary methods, or in the other plastic arts.

1 have discovered that an adequately strong and useful solvent may be prepared by mixing the lower monohydroxy aliphatic alcohols (which are not strong enough solvents by themselves) with monochlornaphthalene. The combination of ethyl alcohol and chloroform with monochlornaphthalene has been previously described, but I have dis covered that the chloroform, which is relatively the most expensive of the ingredients, can be omitted.

While the proportions of my compound solvents may be greatly varied. I prefer those in which the monochlornaphthalene and lower monohydroxy aliphatic alcohols are present in substantially equal proporea tions. Methyl alcohol, ethyl alcohol and iso- Application filed April 5, 1921. Serial No. 458,787.

propgl alcohol are typical examples of the liqui s which may be mixed with the monochlornaphthalene. I may also vary considerably the amount of ether that is dissolved in"the"compound solvent. By way of example, I may dissolve 1 part by weight of water-insoluble ethyl cellulose in 5 parts of the solvent, obtaining a thick viscous flowable solution. Other substances which impart additional suppleness to the film-may then added to the dope, such, for instance, as triphenyl or tricresyl phosphate, camphor, etc.

The ingredients are of the ordinary commercial type and sufiiciently purified for the process of film manufacture, so as to give a dope yieldingfilins having the proper relative freedom from color. The viscous-flowable dope above described can be used in connection with the usual film-forming apparatus without the necessity of expensive alterations in the latter. The homologues of monochlornaphthalene and its isomers act equivalently, including the monochloranthracenes, etc. By the term lower monohydroxy aliphatic alcohols, I include such alcohols containing less than 6 carbon atoms.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A compound solvent for alkyl ethers of cellulose, consisting of a mixture of monochlornaphthalene and a lower monohydroxy aliphatic alcohol.

2. A compound solvent for alkyl ethers of cellulose, comprising approximately equal parts by weight of monochlornaphthalene and of a lower monohydroxy aliphatic alcohol.

3. A viscous flowable film-forming composition, comprising an alkyl ether of cellulose dissolved in a mixture consisting essentially of monochlornaphthalene and a lower monohydrox'y aliphatic alcohol.

4. A viscous flowable film-forming composition, comprising an alkyl ether of cellulose dissolved in a compound solvent consistingessentially of substantially equal parts of monochlornaphthalene and a lower monohydroxy aliphatic alcohol.

5-. A composition of matter, comprising water-insoluble ethyl cellulose dissolved in a compound solvent consisting essentially of nionochlornaphthalene and ethyl alcohol.

6. A composition of matter, comprising Q memes water-insoluble ethyl cellulose dissolved in not of the hydrocarbons C H and their a compound solvent contaimng approximatehomologues, and a. lower monohydroxy alily equal parts by Weight of monochlornaphphatic alcohol. 10

thalene and ethyl alcohol. Signed at Rochester, New York, this 26th 5 7. A composition of matter, comprising day of March, 1921.

cellulose other dissolved in a compound consisting of a chlor nucleo substitution prod- STEWART J. CARROLL. 

